The present invention relates to a forming device of a preimpregnated material produced by impregnating thermosetting resin to carbon fiber or glass fiber and the like.
A technique for utilizing preimpregnated material produced by impregnating thermosetting resin such as epoxy resin and phenolic resin to long fiber such as carbon fiber and glass fiber to form a product having the desired cross-sectional shape by heating and forming the material is known. Since carbon fiber and glass fiber have great strength, especially tensile strength, per unit weight, a composite material formed by laminating fiber material with the fibers oriented in vertical, horizontal and diagonal directions can be used to manufacture products having light weight and relatively high strength and elasticity. Therefore, the material is widely utilized in forming aircraft and other industrial products.
The material used for forming the desired shape can be manufactured by arranging carbon fiber or glass fiber impregnated with thermosetting resin in parallel orientation to form one layer, by using fabric produced from these fibers to form one layer, or by laminating a plural number of such layers, further positioning roving of these fibers between layers if necessary to produce the forming member. The forming method and forming device of this material includes feeding plural strip-shaped preimpregnated materials from bobbins, heating and pressurizing the material by heated upper and lower molds of a hot press device to form a predetermined cross-sectional shape, an then curing the formed product in a curing furnace and completing the product. During the above-mentioned forming steps, the product is continuously pulled (hauled) by a haulage device mounted to the downstream side in the forming device so as to convey the product in the forming device.
However, the problems of the conventional forming method and device explained above is that notable friction resistance is generated when pulling the formed product by the haulage device, causing abrasion such as cutting or curling of the fiber. Furthermore, since the hauling force of the haulage device is strong, it is difficult according to the conventional method and device to form a thin product. Therefore, in order to solve these problems, the present applicants proposed, in Japanese Patent Laid-Open Application No. 2-102029, a device for intermittently transmitting strip-shaped preimpregnated material while bending the material with a mold so as to form a channel-shaped cross section, and hot-pressing the material to form a product with the desired shape. The device enables to continuously form structural members having linear trajectory with L-shaped or U-shaped cross section. The forming device of this kind is also disclosed in the specification of U.S. Pat. No. 4,151,031.
The present invention provides a device for efficiently forming H-shaped members made of FRP with advanced performance that can be used for underfloor beam member or reinforcement of main and tail planes of an aircraft.
The continuous forming device of an H-shaped FRP member according to the present invention comprises a device for mounting a plural number of bobbins having strip-shaped preimpregnated material produced by impregnating thermosetting resin to carbon fiber or glass fiber and the like spooled thereto, a device for providing tension when pulling the preimpregnated material out from the bobbin, a device for shaping the preimpregnated member to a predetermined H-shape, a device for feeding release films from four (upper, lower, left and right) sides, a press device for providing heat and pressure to the preimpregnated member from four sides, a heating furnace for after-curing the preimpregnated member, a device for hauling and holding the preimpregnated member, and a device for cutting the cured product to predetermined lengths.
Further, the device for shaping the strip-shaped preimpregnated member provided from the bobbins to form a predetermined H-shape comprises a device for forming two creases to two sheets of preimpregnated material in the longitudinal direction, a device for bending the sheet at the creases to form an open-trapezoid-shaped cross section, and a device for forming a U-shaped cross section and further superposing two U-shaped preimpregnated members to form an H-shape.
Moreover, the haulage device is interlocked with upper, left and right molds of the press device so that the preimpregnated member is heated and pressed for a predetermined time before being hauled for a predetermined length, and the press device is equipped with means for controlling the sequence for opening and closing the upper, left and right molds.